[PATCH] D45383: Limit types of builtins that can be redeclared.

[Erich Keane via Phabricator via cfe-commits]

erichkeane added a comment.

In https://reviews.llvm.org/D45383#1069049, @efriedma wrote:

> We can could add an exception to the "don't allow redeclarations with custom type-checking" rule to specifically allow redeclaring `__va_start`.  The general rule is that we don't want user code redeclaring them because they don't have a specific signature, so our internal representation could change between releases.  But `__va_start` has a specific fixed signature from the Microsoft SDK headers, so it should be fine to allow redeclaring it without a warning.


That still doesn't fix the bug, since redeclaring __va_start in 'C' mode when va_list is a reference type causes the assert.


https://reviews.llvm.org/D45383